Seiko Men's Astron GPS Solar Dual Time Watch is the perfect timepiece for the global traveler. Seiko new Astron 5X Series is smaller, thinner, faster and more intuitive than ever. Seiko Astron 5X series is the world's smallest and thinnest GPS solar watch. Like all predecessors the new Astron 5X series adjusts at the touch of a button to your time zone, by connecting to the GPS satellite network and, as it takes all the energy it needs from the light alone, it never needs a battery change and yet delivers that astonishing precision of an atomic clock, one second every 100,000 years.